Annelise Folie, Florias Mees, Thierry De Putter, and Thierry Smith (2016)
A new large species of the snake Palaeophis from the Lutetian marine margin of the Congo Basin, Cabinda, Angola
In: Society of Vertebrate Paleontology October 2016, ed. by Andy Farke; Amber MacKenzie; Jess Miller-Camp, vol. Astracts of papers 76th Annual Meeting, pp. 137, Society of Vertebrate Paleontology.
Numerous fossil localities were investigated in western central Africa during the Belgian expeditions that started in the 19th century. At least 47 localities were excavated or analyzed in the framework of Edmond Dartevelle’s paleontological expeditions of 1933 and 1937-1938, producing a large and unique collection of Mesozoic-Cenozoic vetebrates from the margin of the Congo Basin along the coastal area of Angola to Gabon. Among them, snake vertebrae from the marine Paleocene-Eocene Landana section, Cabinda enclave, Angola have been referred to the aquatic snake Palaeophis aff. typhaeus. New investigation of the old Dartevelle’s collections has led to relocation of a few undescribed snake vertebrae from Landana and the nearby locality of Sassa Zao, permitting a revision of Palaeophis aff. typhaeus. The results of this work indicate that all specimens from Landana originate from the same stratigraphic level (layers 31-32) and are of Lutetian age based on the rich associated elasmobranch fauna. The locality of Sassa Zao is also Lutetian based on elasmobranchs that are similar to those of layer 32 of Landana. All of the vertebrae, ten in total, can be attributed to a single large species of Palaeophis. The maximum width across the prezygapophyses is 35 mm and the maximum length of the centrum is 27 mm. The weak lateral compression of trunk
vertebrae, low development of the pterapophyses, diapophyses not very low, and the marked lateral projection of the zygapophyses indicate that this species belongs to the ‘primitive’ grade of Palaeophis and thus differs from species of the ‘advanced’ group such as P. casei, P. ferganicus, P. littoralis, P. toliapicus, P. typhaeus, P. grandis, P. tamdy, P. nessovi, and P. udovichenkoi. Among ‘primitive’ grade species, it differs from the giant P. colossaeus by smaller size, proportionally longer vertebrae, the cotyle and condyle more oval in shape, and the zygosphene not larger than the cotyle; from P. africanus by the neural spine that does not approach the zygosphene and shorter hypapophyses that are not prolonged by a ventral carina; from P. vastaniensis, P. virginianus, and P. zhylan by less depressed vertebrae. In size and morphology it most closely resembles P. maghrebianus but differs by more developed hypapophyses and paradiapophyses that do not extend over the cotyle posteriorly. This new species was apparently poorly adapted to aquatic life and was more closely related to the North African Ypresian P. maghrebianus than to West African Lutetian species.
Grant Information
This abstract is a contribution to the project BR/121/A3/PalEurAfrica funded by the Belgian Science Policy Office.
Peer Review, International Redaction Board, Impact Factor, Abstract of an Oral Presentation or a Poster
Paleontology
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